Electrolominescent display device with semiconducting polymer

Abstract

A drive of a display device based on polymer LEDs, for example pixels arranged in the form of a matrix, in which the lifetime is increased by writing the information from an interlaced signal each time into two successive rows. The driving may be based on voltage control at which voltages across the pixels define the picture to be displayed, but may alternatively be based on current control.

We claim: 
     
       1. An electroluminescent device comprising a first pattern of electrodes, a second pattern of electrodes, at least one layer of a semiconducting conjugated polymer interpositioned between the first and second patterns of electrodes, at least one of which electrodes is transparent to light to be emitted from the polymer layer, the first pattern comprised of a material which is suitable for injecting holes or electrons into the polymer layer, characterized in that one of the first and second patterns of electrodes comprises row electrodes and the other pattern comprises column electrodes situated cross-wise with respect to the row electrodes, the areas of crossing defining pixels in the interpositioned polymer layer, and further characterized in that the device comprises a drive circuit for presenting drive voltages representing rows of picture information derived from successive odd and even fields of picture information to the row electrodes, the drive circuit comprising means for presenting drive voltages representing an nth row of picture information from an odd field simultaneously to an nth row electrode and to an adjacent row electrode, and next presenting drive voltages representing an adjacent row of picture information from an even field simultaneously to the an nth row electrode and to an adjacent row electrode, whereby each nth row of pixels is alternately presented with drive voltages representing the nth row of picture information and an adjacent row of picture information. 
     
     
       2. An electroluminescent device as claimed in claim 1, for displaying successive rows of picture information, wherein during two successive field periods, the drive circuit provides an nth row electrode with drive voltages representing the nth row of picture information and the (n+1)th row of picture information.